Machine for molding building blocks of concrete or like cementitious material



Dec. 12, 1950 R. LEGGAT 2,533,479

MACHINE FOR MOLDING BUILDING BLOCKS 0F CONCRETE 0R LIKE CEMENTITIOUS MATERIAL Filed July 22, 1948 2 Sheets-Sheet 1 3 B 4 a O /4L7 f--\/ A W A v W l 6 T l 7 8 2o 30 HG I I I n l8 ROBERT uses BY Z HTTORN EV Dec. 12, 1950 2,533,479

- R. LEGGAT MACHINE FOR MOLDING BUILDING BLOCKS 0F CONCRETE 0R LIKE CEMENTITIOUS MATERIAL Filed July 22, 1948 2 Sheets-Sheet 2 FTGYII II I I II I I we H I 15- Q P i' zs IO 13 30 Fe 1y INVENTOR.

ROBERT LEGGHT Patented Dec. 12, 1950 MAOHIN-EFOR MOLDJZP-IG BUILDING BLQCKS OF CONCRETE 1 OR LIKE CEP' IENTITIGUS MATERIAL Robert Leggat, Pretoria, Transvaal, Uniun of South Africa ApplicationJuly'ZZ, 1948, Serial No. 40,136 in the Union.of5outh Africa- August 12, 1947 i This invention relates to a machine for moulding building blocks from concrete or like cernentitious material and in particular to a manually operated machine.

The object of the invention is toprovide a machine capable of producing blocks comprising two slabs which in their vertical and normal position are fastened together by transverse ties having their ends moulded into the slabs and for producing modified forms of similar blocks such as are used for corners and other positions in a building. Said blocks have their ends and top and bottom surfaces shaped to lock into contiguous blocks.

The machine according tot-his invention consists in a moulding box having a fixed base and a hinged cover.

The two sidewalls and the front Wall are hinged to fall away from the moulded block and the base of the box is perforated to enable the core and the end. and. any special side moulds to be withdrawn downwardly. Removable platens are provided to form the underside and support for the finished block, the'c'o'ver carries moulds to finish the topof the block and provision is made for the insertion of relieving strips to ease the downward withdrawal from the block of the end moulding pieces.

The moulds at the ends and, where necessary, in the side walls of the box are made replaceable to enable the machine to be used for blocks of different shapes to suit their position in the building.

The invention is illustrated by the accompanying diagrammatic drawings in which:

Fig. I is a side elevation of the machine.

Fig. II is a plan on A-A Fig. I.

Fig. III is a section on 3-3 Fig. I.

Fig. IV is a similar view to Fig. I but with parts in the open position.

Fig. V is a detail of a core for the block.

Fig. VI is an isometric view of a block of normal shape.

Fig. VII is a plan view of one modified form of block.

Fig. VIII is an isometric view of a pallet for the lock of normal shape.

In the drawings I is the moulding box, rectangular in form, mounted in a frame 2 and provided with a lid 3 hinged at 4. The two side Walls 5, 5 and the end wall I are hinged at 8 so that they may be made to fall away from the moulded block.

The end 9 remains rigidly connected to the frame 2. The base It of box I is fixed in position to frame 2 but it is perforated so that core 2 Claims. (Cl. 25--41) block while mounted on pallet 24.

I I for the block passesthrough it. I2 is a plate which carries core H and can be moved close up under base it or be carried downwardly so as to withdraw the core H from the box I. Such movement is made by lever I3 and link M. Mounted on and fixed to plate I2 are end moulding forms [5, It for forming the ends of the block. The base Iii is perforated for theirpassage and rigid slides H, I8 allows for theirsupport and easy sliding movement.

In addition form moulds IH-may be-fixed where necessary at the sides of the box and be secured to plate I2 and guided by slides 20.

The lid 3 on its under side is provided with moulding pieces 21 to form a ridge 22 on the top of the block to correspond with the groove 23 made in the bottom of the block which is formed by a pallet 24 placed on the base iii-of the-box I. 25 are transverse recesses adapted to receive the prongs of a liftingfork for the removal of th The core H is slotted down half way by slots 23 into which maybe passed ties 2!- for holding together the two slabs 25, 2s forming the shape of the normal block. A suitable catch 39 is provided to hold up the lever l3.

35- shows relieving strips of spring brass or similar material which are used on the face of the form iii. They are secured at their top ends in recesses in the top of end member 5, as indi sated in Fig. IV. Their purpose is to form a relieving clearance between the block face 33 and the form it and prevent tearing of the surface of the moulded block when the form it with-the core and form I5, and iii if used, are withdrawn by the lowering of plate i2. In other words the strip remains stationary when the form 56 is moved downwardly from the moulded block, but holds the block consolidated.

The normal blocks made by this block moulding machine are as mentioned above made of two slabs 28, 29 having their top faces 32 provided with ridges 22 and their bottom faces 34 with corresponding recesses 23.

The ends 35, 35 are normally formed with the complementary shapes of a male and female dovetail 3?, 33, so that on assembly they may lock together.

The forms i5, it may be replaced by forms of other shape which will leave the moulded block undamaged when they are removed by a downward movement. For example for moulding the block shovro in Fig. VII, the form i5 is changed for a mould providing a form of block hown at 9. Said block or any other form of block may have a dovetail recess 4| placed on its side so that when used at the corner of a building the block in the wall at right angles to it may be locked in place. To provide the recess the form [9 sliding on 20 may be used. Conveniently when form I9 is used on a block as shown in Fig. VII, it is extended inwards to form the gap 42 in the block In the case of the block as shown in Fig. VII the core I I must be shortened in a manner well known in the trade. It is convenient for this purpose to have the core made up of sections such as 43, 44, 45 as shown in Fig. V, 50 that any portion may be withdrawn. The width of the sections will be determined by the particular shape of block required.

Innumerable moulding forms may be used in the box I for forming the difierent shaped blocks required in a building.

In use the moulding forms are fastened in position to plate l2. Plate I2 is raised also the walls of the box which are tied together as by suitable latches at 46. The ties 21 are slipped into place, the relieving strips 3| are properly positioned, and a measured or weighed quantity of the cementitious material, which should be of a damp sandy consistency, run in between the core II and the side walls 5, 6. When the box is full the cover 3 is slammed down to beat the material down into the box I Because the hinge 4 of the lid 3 is towards the form I 6 the material tends to pack tighter towards l6 than towards I hence the use of the relieving strips 3| at this end. 41 is a handle for use in slamming down the lid 3.

If desired when the block has received its initial compression one or other of the sides 5, 5 or I may be lowered to enable the moulded block to be inspected. It is known to give moulded blocks a surface of, for example, plaster or of special stone or other chippings and when desired such a surface may be placed in position during this inspection by any known method, and before the box is reclosed.

When the material has been tamped down by the lid 3 until the lid descends fully onto the top of the moulding box I the block is properly moulded. The lid 3 is lifted and the core II and the forms I5, I6, and I9 if used, are withdrawn downwardly by the lowering of plate I2. These parts are relieved slightly upwardly of their height in the well known manner to facilitate such withdrawal. That is, they taper very slightly towards their top edges. The three sides 5, 6, I are lowered and the block is lifted out on its pallet 24 and stacked for maturing. The parts of the machine are again placed in position to enable the next block to be moulded.

This invention provides a manually operated machine for moulding building blocks, which may, if desired, be made in special and variable shapes.

What I claim as new and desire to secure by Letters Patent is:

1. A machine for moulding building blocks comprising a moulding box, a frame supporting the box, a base for the box, and a side of the box rigidly fixed to the frame, three sides of the box hinged to the frame, a support below the base, a slotted core and moulding form, mounted on said support and perforating said base, a pallet resting on said base, a lever and linkages lowering said support, a lid for the box hinged to the side of the box fixed to the frame of the machine, and relieving strips facing the moulding forms on the side to which the lid is hinged.

2. A machine for moulding building blocks comprising a moulding box, a frame supporting the box, a base for the box, and a side of the box rigidly fixed to the frame, three sides of the box hinged to the frame, a support below the base, a slotted core and moulding forms mounted on said support and perforating said base, a pallet resting on said base, a lever and linkages lowering said support, a lid forthe box hinged to the side of the box fixed to the frame of the machine, and relieving strips facing the moulding forms on the side to which the lid is hinged and fixed to the fixed side of the box.

ROBERT LEGGAT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 903,908 Soss Nov. 17, 1908 937,627 Moore et al Oct. 19, 1909 2,280,635 Ishman Apr. 21, 1942 

